The present invention relates to a fully automated method and apparatus for manufacturing a wiring harness, and particularly to apparatus for paying out wires to predetermined lengths after the leading ends are loaded into a connector block.
Harness making apparatus of the prior art generally comprise means for mass loading the leading ends of a plurality of wires into connector blocks having insulation displacing terminals therein. See, e.g., U.S. Pat. Nos. 4,043,017, 4,136,440, and 4,235,015. After the leading ends of the wires are loaded into a connector block, it is usually desirable to vary the lengths of the wires before shearing to form the trailing ends. This is accomplished by means of looping members which deflect the wires between the loaded connector block and the wire source to form loops of various lengths. The looping members may be in the form of blades, as in U.S. Pat. No. 4,136,440, or rollers, as in U.S. Pat. No. 4,235,015. Both require towers with an individual member of adjustable height for each looping member. The members are manually adjusted so the relative heights of each vary, and the towers move vertically as a unit.
While the deflecting towers of the prior art have been used with harness making apparatus of the type using insulation displacing connectors, use of such towers would be equally applicable in apparatus of the type disclosed in U.S. Pat. No. 4,363,167. That application discloses apparatus for terminating wires and insertion of the terminated wires into a connector block, said apparatus using a reciprocating wire feed shuttle having telescoping wire guide tubing which prevents wire buckling under forces sustained during insertion. While such towers have been effective, the drawbacks are that they are only manually adjustable, they take up considerable space in the area of termination, and highly accurate control of loop length is not readily attained.